package com.xyz.springcloud.lb;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * 让容器扫描到相应的内容
 * （把普通pojo实例化到spring容器中）
 */
@Component
/**
 * @author 肖咉卓
 */
public class MyLb implements LoadBalancer {

    private AtomicInteger atomicInteger = new AtomicInteger(0);

    /**
     * 获得访问次数
     * @return
     */
    public final int getAndIncrement(){
        int current;
        int next;
        do{
            current = this.atomicInteger.get();
            next = current >= 2147483647 ? 0 : current + 1;
        }while (!this.atomicInteger.compareAndSet(current,next));
        System.out.println("****第几次访问，次数next:"+next);
        return next;
    }

    @Override
    public ServiceInstance instances(List<ServiceInstance> serviceInstances) {
        //获得要执行服务器的下标
        int index = getAndIncrement() % serviceInstances.size();
        return serviceInstances.get(index);
    }
}
